text: The experiment setup contains 3 parts: an inhomogeneous magnetic field in front, the rotating field at the middle, and another inhomogeneous magnetic field at the end.
  Atoms after passing the first inhomogeneous field will split into 2 beams corresponding the spin up and spin down state. Select one beam (spin up state, for example) and let it pass the rotating field. If the rotating field has frequency (ω) equal to the Larmor frequency, it will produce a high intensity of the other beam (spin down state). By sweeping the frequency to obtain a maximum intensity, one can find out the Larmor frequency and the magnetic moment of the atom.